Method for the production of nuclear substituted cinnamoylanthranilic acid derivatives

摘要

The present invention provides an improved method for producing a nuclear substituted cinnamoylanthranilic acid compound. Illustrative of the process is the reaction of 3,4-dimethoxybenzaldehyde with 2-carboxymalonanilic acid in an inert solvent medium in the presence of piperidine to provide an intermediate salt precipitate, and the salt is treated with an acidic reagent to yield N-(3,4-dimethoxycinnamoyl)anthranilic acid product.